Keywords

Deep excavations, Inclinometers, Diaphragm Walls, Dewatering, Urban Environment, Back-analysis

Abstract

This paper studies the deformations caused by a deep excavation in an urban environment. The case study involves an underground parking garage in the historical center of the Dutch town of Leiden, characterized by a high water level and soil layers containing clay, silt, and peat. The design of this kind of structure in these conditions is usually accompanied by a lot of uncertainties. Therefore, a thorough comparison of the structure’s expected behavior and its actual behavior is very useful to improve the accuracy of future calculations. With this in mind, the predictions based on different calculation methods are compared to both inclinometer-measured deformations of the garage itself and settlements of historical buildings around the excavation. Both a back-analysis and a sensitivity analysis are carried out, taking into account the most important influence factors for the excavation. Based on this analysis, recommendations are made for increased accuracy of future calculations.

DOI